mirror of
https://github.com/gonum/gonum.git
synced 2025-10-31 10:36:30 +08:00
ec100cf00f
Improved function documentation Fixed dlarfb and dlarft and added full tests Added dgelq2 Working Dgels Fix many comments and tests Many PR comment responses Responded to more PR comments Many PR comments
29 lines
644 B
Go
29 lines
644 B
Go
// Copyright ©2015 The gonum Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package native
|
|
|
|
// Iladlr scans a matrix for its last non-zero row. Returns -1 if the matrix
|
|
// is all zeros.
|
|
func (Implementation) Iladlr(m, n int, a []float64, lda int) int {
|
|
if m == 0 {
|
|
return m - 1
|
|
}
|
|
|
|
checkMatrix(m, n, a, lda)
|
|
|
|
// Check the common case where the corner is non-zero
|
|
if a[(m-1)*lda] != 0 || a[(m-1)*lda+n-1] != 0 {
|
|
return m - 1
|
|
}
|
|
for i := m - 1; i >= 0; i-- {
|
|
for j := 0; j < n; j++ {
|
|
if a[i*lda+j] != 0 {
|
|
return i
|
|
}
|
|
}
|
|
}
|
|
return -1
|
|
}
|